Summary of Impact: Between 19:36 and 22:28 UTC customers may have experienced issues with delayed delivery and/or non-imprinted email due to widespread Microsoft network issues.
Root Cause: Microsoft experienced issues with their DNS service as summarised - https://azure.microsoft.com/en-gb/status/history/. This issue caused internal routing issues between Microsoft 365 and Microsoft Azure services and therefore Exclaimer Cloud was not able to route messages back to 365 correctly.
Mitigation: Microsoft resolved their global issue and service was restored.
Next Steps: We are working with Microsoft to understand the issue in more detail and if Exclaimer Cloud can be more resilient to these sorts of issues in the future.